Now entering its seventh year onstage, “Jersey Boys” is a wildly popular musical revealing the behind-the-scenes story of Frankie Valli and The Four Seasons. Intrigued by its ongoing ubiquity, we sat down with book writers Rick Elice and Marshall Brickman to discuss how this hit came about and what elements contributed to its indisputable success.

Unsurprisingly, the music was the main selling point. “A friend of mine had the rights to the catalog of The Four Seasons songs and said, ‘How would you like to write a musical about Frankie Valli?’” recalls Elice. “I said, ‘You mean the guy with the really high voice?’ He started rattling off these song titles, all of which I knew, never associating them with the same group. I said, ‘Marshall Brickman and I have been looking to write something.’”

Elice and Brickman had never professionaly collaborated — and neither one had experience writing a Broadway musical. So Elice simply told his friend, “We’ll see what can happen.”

The resulting play follows the release time line of radio favorites such as “Sherry,” “Walk Like A Man” and “Can’t Take My Eyes Off Of You,” and is subsequently known as a jukebox musical — a stigmatic label in the arts world.

“Theater has always been about adaptation,” Elice reminds. “It’s just about how you’re going to tell it.” Brickman agrees, arguing: “Nothing in life is a documentary. Anytime you’re exercising editorial discretion, it’s not truth anymore.”

So what are the challenges of conveying someone’s story when they’re still around to see it? (Valli is now 77 years old and still touring.)

“There was a bit of negotiation going on,” admits Brickman. “We had to change some things at the request of Bob [Guardio] and Frankie — which we happily did.” He adds slyly, “Everybody has an ego, and everybody has an ex-wife.”

So what’s up next for this musical? The second national tour recently started in Philadelphia. And in?April, the show will debut in Auckland, New Zealand. Valli has also booked two weeks of gigs there. “[You can tell] he’s excited, because he’s taking a very long plane trip,” jokes Elice.

Offstage, a “Jersey Boys” movie adaptation is in the works for 2014.

Fast facts

It’s the 21st longest-running show on Broadway.

It won four Tony Awards, including Best Musical in 2006.

It’s been seen by more than 13 million people worldwide.

It’s one of the highest-grossing weekly shows on Broadway.

It raised more than $1.2 million for Broadway Cares/Equity Fights AIDS.